This application proposes to conduct a five-year study to monitor HIV risk behavior and evaluate the effectiveness of an enhanced intervention to combat the spread of HIV infection among targeted populations in New Orleans. The targeted populations include intravenous drug users (IVDUs), prostitutes who trade sex for drugs or money, crack cocaine users, and the sexual partners of IVDUs, prostitutes, and crack users. All participants in the proposed study will be drawn from ten large public housing projects in New Orleans. The study will employ a quasi-experimental design in which the ten housing projects will be matched on important characteristics into pairs. One of each pair of matched projects will be randomly assigned to an experimental (i.e., "enhanced") or control (i.e., "standard") intervention condition. The experimental intervention, which builds upon our recent research experience in community outreach to IVDUs, will consist of (a) a CDC approved "knowledge-based" intervention protocol provided at our outreach office by trained personnel, (b) additional information on HIV prevention provided at our office, and (c) risk reduction skills-building training provided in six "onsite" sessions that will be conducted with participants on their own turf in the housing projects over a 12-week period. Participants who reside in the five housing projects randomly assigned to the control condition will receive the standard CDC intervention only at our outreach office. After 30 months, the enhanced intervention will be extended to persons drawn from the housing projects in the control condition. Outcome measures will consist primarily of indicators of HIV risk behavior as measured by NIDA's AIA and AFA. In addition, we will assess other potentially important outcomes, such as psychological adjustment, readiness for drug treatment, number and length of drug treatment episodes, etc. Process measures will include assessment of level of treatment implementation and across-condition contamination. Multi- variate and tabular analyses will be used to assess the initial comparability of participants from the pairs of housing projects, measure the reactivity of the AIA and AFA with the intervention, and evaluate the effectiveness of the enhanced intervention. The evaluation will consider the extent of exposure to the enhanced intervention as well as significant differences between the baseline characteristics of participants from the two conditions in each housing project pair.